The present invention relates to a cursor displaying technique in a multi-display system.
In the multi-display system to which the present invention is directed, plural sets of displays and display control units respectively associated therewith, a plurality of displays are physically juxtaposed to form a single seamless large display, and a single cursor is smoothly movable between the plurality of displays.
A conventional cursor display system will be described with reference to FIG. 2.
As shown in 1A and 1B, displays 4 and 5 which are controlled by display control units 2 and 3 are physically closely juxtaposed to form a single, seamless display.
When the multi-display system is driven, then an application program or an operation system issues a cursor generation request. In response to the request, cursor generating means 6 computes a hot spot, a cursor pattern, and the like to generate a cursor pattern 7. The generated cursor pattern 7 is transferred to cursor display means 8 and 9 of the display control units 2 and 3.
The display control unit 2 or 3 controls the individual display 4 or 5 by the application program, and depicts a picture in accordance with a request by the application program, and those display control units have their own cursors, respectively. A specific example to which the present invention is applied is Windows NT work station of Microsoft Corporation.
To realize a smooth movement of a single cursor between the displays 4 and 5, the cursor generation request and the cursor movement request are transferred to the display control units 2 and 3, the display control units 2 and 3 move their own cursors to a designated position in consideration with the display positions of the displays and 4 and 5 assigned in control to those control units. More specifically, when the designated position is within a display control area of one of the display control units, the cursor is moved to the display control area. When it is not within the display control area, the cursor is put out. As a result, a single cursor is displayed in the composite display, and in this state, a cursor movement request is issued, so that it is smoothly movable.
A cursor movement request that is issued from a relative coordinate device, e.g., a computer mouse, is designated by the coordinates of a point of the cursor, called a hot spot. Usually, the cursor display means control their individual displays, respectively. When the hot spot coordinates of a cursor movement request are designated so as to be out of the display control area of one of the display control units, the display control unit corrects the hot spot coordinates so that the hot spot defined by the coordinates is located within its display control area or the cursor having such a hot spot is put out, in order that the cursor is confined within the display control area of the display control unit. In the windows NT work station, for example, when the hot spot coordinates that are not within its display control area, the coordinates are automatically processed to be within its display control area.
In the multi-display system mentioned above, when a cursor movement request containing a hot spot to be placed at the boundary between the individual displays, a cursor pattern having the hot spot is correctly displayed within the display control area within which the coordinates of the hot spot are located. However, when the hot spot is somewhat out of the display control area, the coordinates of the hot spot are corrected to be within the display control area or the cursor is put out in display. The resultant cursor displayed does not take an exact pattern of a single cursor, as shown in the displays 1A and 1B.
As described above, the conventional cursor display technique is disadvantageous in that when the cursor moves past the boundary between the individual displays, which are to be combined, the cursor pattern displayed changes to give rise of unnatural visual feeling.
Accordingly, an object of the present invention is to provide a seamless display without any deformation of a cursor pattern displayed when a cursor moves past a boundary of the individual displays combined into the seamless display, without any alteration of the display control units.
According to the present invention, there is provided a first A cursor display device for use with a multi-display system having a plurality of displays, display control units for controlling the displaying operations of the displays, wherein the plurality of displays are closely juxtaposed, the cursor display device comprising: cursor generating means for generating, upon a cursor generation request, four individual cursor patterns, equal in configuration, having hot spots located at the upper left, the upper right, the lower right and the lower left coordinate points in a cursor pattern rectangular, and for attaching to the hot spots offset values as attribute values of the hot spots; and cursor transforming means which compares, upon a cursor movement request, the relative positions on display ranges, cursor-display designation coordinates, and cursor pattern sizes, selects an intended cursor from the four cursors, and adds an offset value to the cursor-display designation coordinates of the selected cursor.
A second cursor display device for use with a multi-display system is based on the first cursor display device, specified such that when a configuration of the selected cursor is within a display control area of the cursor transforming means, but the cursor display designation coordinates of the selected cursor is not within the display control area, the cursor transforming means detects a position in the display control area to which the cursor display designation coordinates have shifted, and when the detected position is located in the upper portion, the cursor transforming means selects the cursor of which the hot spot is located at the lower right or lower left coordinate point, when the detected position is located in the lower portion, the cursor transforming means selects the cursor of which the hot spot is located at the upper right or upper left coordinate point, when the detected position is located in the right portion, the cursor transforming means selects the cursor of which the hot spot is located at the upper left or lower left coordinate point, and when the detected position is located in the left portion, the cursor transforming means selects the cursor of which the hot spot is located at the upper right or lower right coordinate point.
A third cursor display device for use with a multi-display system is based on the first cursor display device, specified such that the cursor transforming means predicts a cursor movement direction and selects one cursor from the four cursors in advance.
A fourth cursor display device for use with a multi-display system having a plurality of displays, display control units for controlling the displaying operations of the displays, wherein the plurality of displays are closely juxtaposed, the cursor display device comprising: cursor transforming means which compares, upon a cursor movement request, the relative positions on display ranges, cursor-display designation coordinates, and cursor pattern sizes, sets the hot spot of the cursor generated by the cursor generating means to any of the upper left, the upper right, the lower right and the lower left coordinate points in a cursor pattern rectangular, and adds the offset value to the cursor-display designation coordinates of the selected cursor.